Drafting pen with dried ink collector

ABSTRACT

A drafting pen of the type having a barrel enclosing an ink reservoir with an axially aligned vent hole in its top and an ink capillary passage in its bottom and including a valving stem axially reciprocal within said vent hole at the top and having a cleaning wire at its bottom engaging said capillary passage. The invention includes a modification of the valving stem and the vent hole so as to collect dried ink within the vent hole, then displace the ink longitudinally above and away from the vent hole.

United States Patent FOREIGN PATENTS 1,073,878 6/1967 Great Britain.... 401/258 597,184 8/1959 ltaly 401 759 Primary Examiner- Lawrence Charles Attorney-David H. Semmes ABSTRACT: A drafting pen of the type having a barrel enclosing an ink reservoir with an axially aligned vent hole in its top and an ink capillary passage in its bottom and including a valving stem axially reciprocal within said vent hole at the top and having a cleaning wire at its bottom engaging said caplllary passage. The invention includes a modification of the valving stem and the vent hole so as to collect dried ink within the vent hole. then displace the ink longitudinally above and away from the vent hole.

PATENTED AUG 1 0 mi 3 595,494

sum 1 or 4 f 12 ll PATENTEU AUG 1 0 I97! sum 3 or 4 DRAFTING PEN WITH DRIED INK COLLECTOR BACKGROUND OF THE INVENTION Field of the Invention Drafting or scribing pens are conventionally provided with an ink reservoir and a tubular writing point communicant with the reservoir via a capillary passage. This ink reservoir also may be provided with a vent hole to permit air to circulate to and from the ink reservoir.

Difficulties are encountered sometimes with a vent system having a manually operable vent stem, since dried ink collects in the vent hole and blocks air circulation through the vent hole. Removal of this collected ink is possible, but the removed ink collects on top of the vent hole and after a short period of time, accumulated particles of dried ink can prevent good air circulation through the vent hole. As a result, the total vent system may have to undergo thorough and time consuming cleaning.

SUMMARY OF THE INVENTION According to the present invention, the pen barrel is provided with an ink reservoir which is located in the writing nib immediately adjacent the tubular writing point. The necessary regulation of air, admitted to the reservoir is controlled by a vent stern, which extends axially through the reservoir vent opening and into the reservoir where it is connected with the cleaning wire. Thus, the vent stern serves also to displace the cleaning wire longitudinally, providing a fast and complete cleaning of the ink passageway in the tubular point. Both venting and cleaning are controlled by an adjusting knob extending from the vent stem laterally through a slot in the side of the pen barrel or through an opening on top of the barrel.

In the normal rest position of the adjusting knob the valving portion of the vent stem is downwardly removed from the vent opening. The top of the valving portion is shaped such that ink, which collects on the top in the form of a dried ink layer, stays on this top until a vertical cone of dried ink has built up. As the cone of dried ink puts a bigger grip on the inside wall of the vent opening then on the valve top, the cone breaks off from the vent valve. Then, as the vent valve is moved downwardly, the broken cone of dried ink stays in the vent opening and can be upwardly displaced in one piece and away from the vent opening, by reciprocation of the vent stem through and above the vent opening.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is in part an enlarged vertical sectional view and side elevation of a stylographic pen, according to the invention with its lateral adjusting knob shown in the rest position with the vent open. FIG. 1A through 1C are schematic drawings showing the vent stem in varying mode of venting and nonventing reciprocation. FIG. 1A is the pen according to FIG. 1, whereby manually the adjusting knob is brought to its lowest vent open position and the cleaning wire 16 extends outwardly through the pen tip;

FIG. 1B is the pen, according to FIG. 1, whereby manually the knob is moved upwardly to its first stop and the cleaning wire is retracted into the ink reservoir.

FIG. 1C is the pen, according to FIG. 1, whereby manually the knob is moved upwardly to its second stop and the vent valve has cleaned the vent opening;

FIG. ID is the pen, according to FIG. 1, whereby by means of a protective cap the knob is pushed upwardly from its rest position over such a distance that the vent valve seals the vent opening.

FIG. 2 is a transverse sectional view of the pen, taken along section line 2-2 of FIG. 1.

FIG. 3 is a transverse sectional view of the pen, taken along section line 3-3 of FIG. 1.

FIG. 4 is a transverse sectional view of the pen, taken along section line 4-4 of FIG. 1.

FIG. 5 is a transverse sectional view of the pen, taken along section line 5-5 of FIG. 1.

FIG. 6 is a transverse sectional view of the pen, taken along section line 6-6 of FIG. 1.

FIG. 7 is a transverse sectional view of the pen, taken along section line 7-7 of FIG. 1. 7

FIG. 8 is a transverse sectional view of the pen, taken along section line 8-8 of FIG. 1.

FIG. 9 is a fragmentary vertical sectional view of the'ink reservoir of the pen, according to FIG. 1, with the ink reservoir axially extended by screw threads for ink refill. 7

FIG. 10 is in part an enlarged vertical sectional view and side elevation of a modified pen.

FIG. 11 is a transverse sectional view of the pen, taken along section line 11-11 of FIG. 10.

FIG. 12 is a transverse sectional view of the pen, taken along section line 12-12 of FIG. 10.

FIG 13 is a transverse sectional view of the pen, taken along section line 13-13 of FIG. 10.

FIG 14 is a transverse sectional view of the pen, taken along section line 14-14 of FIG. 10.

FIG. 15 is a transverse sectional view of the pen, taken along section line 15-15 of FIG 10.

FIGS. 16 A-H are vertical sectional views of the vent opening and vent stem, whereby the buildup of a ink core is shown and such a core by means of reciprocating the vent stem is upwardly removed from the vent opening.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 stylographic pen 10 is shown. This pen mainly consists of vent housing 12, nib l4, pen tip 16 and top cover 18.

Pen tip 14 is by means of screw thread 20 connected with vent housing 12, whereby sealing shoulder 22 prevents a leakage of ink 24 out of ink reservoir 26. In the screw threads 20 of pen tip 16 filling port 28 is positioned, through which ink can be brought into ink reservoir 26 if nib I4 is partly screwed off, as illustrated in FIG. 9.

In vent housing 12 there is an axial vent opening 30, through which opening part of vent stem 32 can pass. Vent stem 32 thereby is connected with stem mechanism 34. Adjusting knob 36 of this mechanism laterally protrudes through longitudinal slot 38 in sidewall 40 of vent housing 12, whereby notches 42 and 44 of stem mechanism 34 are movably guided in side barrel wall 40 having notches 46 and 48, as illustrated in FIGS. 2-5. Furthermore stem mechanism 34 is provided with spring support shoulder 50. Pressure spring 60 with its end 62 abuts shoulder top 58, providing a downwardly directed thrust, which thrust is opposite to that of compression spring 54. Top cover 18 is by means of screw threads 63 attached to vent housing 12. Slot 38 upwardly extends to the screw threads top 64 of vent housing 12. As shown 11 FIG. 1, top cover 18 has exterior screw thread wall 66 adjacent slot 38, whereby lower end 68 of cover 18 acts as a stop 70 to which stop knob 36 can be manually brought against the force of pressure spring 60. Laterally opposite this stop 70 there is slot 72 in the opposite sidewall 74 of cover 18. By unscrewing cover 18 approximately 180, this slot 72 then registers with slot 38 and top end 76 of this slot 72, then acts as a second stop to which stop knob 36 can be brought upwardly against the force of compression spring 60.

The base ends 78 and 80 of compression springs 54 and 60 are clamped in recess 82 in the sidewall of housing 12 see also FIG. 3.

In the rest position of mechanism 34 compression spring 60 rests against stops 84 and 86, see also FIG. 2. Spring 60 in said rest position has a downwardly directed thrust countering the upwardly directed force of spring 54. As a result, a longitudinally exact, rest or balanced position of mechanism 34 is obtained. Connection strip 88 of mechanism 34 protrudes through opening 90 in wall 92 of vent housing 12 into ink reservoir 14 and whereby opening 90 and vent opening 30 are in open communication. Also, strip 88 over a great length is connected with vent stem 32, see also FIG. 7.

Mechanism 34 extends downwardly with its lower part 94 to the bottom of ink reservoir 26, connection hold 96 supporting connection piece 98 of cleaning wire 104 with cleaning wire stem 100 under a light press fit, see also FIG. 8.

Guide flanges 108 and 110, see also FIG. 7, supply together with the guidance of connection strip 88 in opening 90 the required guidance for vent stem 32, so as to secure the right lateral position of this stem towards vent opening 30. This construction ensures registry of parts after a long period of usage of the pen, as housing 12, mechanism 34 and vent stem 32 are made of plastic, nylon, Teflon or a like material.

For further guidance, guide flanges 112 and 114 shown in phantom in FIG. 7, may be used.

Ink collected in vent opening 30 is carried off via channel 109 between flanges 108 and 110.

On top of wall 92 around vent opening 30 vent tube 116 is positioned whereby longitudinal opening 118 engages strip 88 to ensure a good sealing of tube 116, see also FIG. 6.

Top end 122 of tube 116 consists of radially inwardly extending fingers defining throw out notches 124, 126, 128, 130 and 132, see also FIG. 5, enabling tip part 134 to extend flexibly inwardly of vent opening 30.

As illustrated in FIGS. 16 AI-I, top 136 of vent stem 32 is provided with dovetail grooves to enable a good attachment of dried ink on this top.

Knob 136 is downwardly displacable against the force of compression spring 54 towards stop 140, as is indicated in FIG. 1A.

'Thus, the bottom end 142 of cleaning wire 104 extends outwardly of pen tip 16. Moving of this wire 104 to its lowest position, also from other knob positions, is necessary periodically to clean the ink capillary passage 106 of dried ink or other collected material. To obtain a quick removal of these particles out of the ink passageway 106, knob 36 first is brought upward against stop 70, as is indicated in FIG. 1B. As cleaning wire 104 then is retracted into i'nk reservoir 26, ink from the ink reservoir then moves in capillary passageway 106. By a repeated further downwardly moving of knob 36 towards stop 140, ink forces the particles out of passageway 106 and at the same time provides a perfect film of wet ink in this passage around needle 104 for writing purposes.

During nonwriting, protection cap. 144 is screwed on the pen bottom, as is shown in FIG. 1D. Thereby, this cap has upwardly displaced knob 36 against force of spring 60, so far that vent stem 32 as a valve has sealed off vent opening 30.

Thereby, lower part 142 of cleaning wire 104 is still within ink passage 106 which prevents ink leakage through this passage.

A clip may be attached to cover 18, as is indicated in phantom FIG. ID, enabling the pen to be carried in a vertical position with pen tip 16 at the lower end. As a result, ink cannot collect in vent opening 30 or even in the compartment above this opening, as it may be drawn out of the ink reservoir during excessive temperature increases. Such ink may be collected in cap 144, which is provided with ink reservoir 145 in its bottom.

During the venting process ink may collect in vent opening 30. Also, after sealing of vent opening 30 by means of vent stem 32 ink can remain in this opening. The construction of opening 30 and vent stem 32 is such that blocking of venting is impossible. Ink, which collects on stem top 136, is carried with the vent stem 32 into ink reservoir 26. See FIGS. 16A and 16B, showing the beginning of the buildup of an ink core on stem top 136 and FIGS. 160 and 16D in the end phase of this core buildup.

If the accumulated dried ink has built up as a core of great longitudinal length, the core will stick against the inside wall 150 of vent opening 30, rather than adhere to stem top 132. When this sticking force is bigger than the attachment force of the ink core on stem top 136, as illustrated in FIG. 16E, downward movement of vent stem 32 results in breaking of the core away from top 136 such that the core remains in vent opening 30, as is indicated in FIG. 16F.

As vent opening 30 then completely is sealed with no writing possibility, this core has to be removed. Removal of the core is shown in FIGS. and 16H with first the upward forcing of the core out of the vent opening 30 by means of vent stem 32 to a position above notches 124- 132 and then during downward displacement of stem 32 and holding of the displaced core by means of the resilient fingers.

The necessarily additional length of upward travel or stem 32 is made possible, as cover 18 is turned about and knob 36 then can move to upper top 76 as is shown in FIG. 1C. As a result, there is obtained an effective and easily cleaned venting system.

In FIGS. 10 and 13 modified pen 10' is shown with the eccentric separation of vent opening 30' from stem passage 90'. Thereby a greater length of connection piece 88' is obtained and notch 152 of mechanism 34 which is movable along the inside wall 154 of ink reservoir 26 now provides the entire guiding of the lower end 156 of mechanism 34, see also FIG. 15. As illustrated in FIG. 11, the well 40' of vent housing 12' also serves as a guide for the upper part 158 of mechanism Iclaim:

l. A drafting pen comprising:

A. a barrel enclosing an ink reservoir having a coaxially extending top venting passage and a bottom ink capillary passage leading to a writing point;

B. a venting stem reciprocably positioned within said reservoir so that a top valving end is seated within said vent passage and a bottom cleaning wire end extends into said capillary passage, said top valving end including:

i. a plurality of serrations adapted to collect dried ink as said vent stem reciprocates in said vent passage.

2. A drafting pen as in claim 1, including:

C. a constricted diameter guard positioned above said vent opening so as to prevent a dried ink core from returning into said vent passage, as said core is reciprocated axially with said vent stem top above said guard.

3. A drafting pen as in claim 2, said guard comprising a plu rality of resilient, radially inwardly extending fingers.

4. A drafting pen as injclaim 3, said vent stem including:

ii. at least one lateral fin engaging a corresponding stabilizing groove in said barrel; and

iii. a lateral adjusting knob extending through a slot in the side of said barrel.

5. A drafting pen as in claim 4, said slot in said barrel being elongated upon movement of said barrel cover.

6. A drafting pen as in claim 5, said venting stem being spring-positioned within said barrel to an open vent position.

7. A drafting pen as in claim 6, including:

D. a cap securable about the bottom of said barrel so as to cover said writing point and urge said lateral adjusting knob upwardly to vent closed position.

8. A drafting pen as in claim 7, said cap including:

E. an ink reservoir communicant said writing point, or said cap placed over said writing point.

9. A drafting pen comprising:

A. a barrel enclosing an ink reservoir having a coaxially positioned bottom ink capillary passage leading to a writing point and a top venting passage;

B. a venting stem including a side adjusting portion and coaxially aligned top venting portion and bottom reciprocally positioned within said reservoir, so that said top valving portion is seated within said vent passage and said bottom cleaning wire end extends into said capillary passage, said top valving end including a plurality of serrations adapted to collect dried ink as said venting portion reciprocates in said vent passage, and said vent stem being positioned with said barrel such that said side adjusting portion is seated eccentrically with respect to said valving portion and includes a lateral adjusting knob extending through a slot in the side of said barrel.

10. A drafting pen as in claim 9, said barrel having a plurality of longitudinal slots in its side, said slots being selectively 11 A drafting pen as in claim 10. said barrel being in separable top, middle and bottom components, such that extension of said bottom component with respect to said middle component provides a lateral filling port into said reservoir. 

1. A drafting pen comprising: A. a barrel enclosing an ink reservoir having a coaxially extending top venting passage and a bottom ink capillary passage leading to a writing point; B. a venting stem reciprocably positioned within said reservoir so that a top valving end is seated within said vent passage and a bottom cleaning wire end extends into said capillary passage, said top valving end including: i. a plurality of serrations adapted to collect dried ink as said vent stem reciprocates in said vent passage.
 2. A drafting pen as in claim 1, including: C. a constricted diameter guard positioned above said vent opening so as to prevent a dried ink core from returning into said vent passage, as said core is reciprocated axially with said vent stem top above said guard.
 3. A drafting pen as in claim 2, said guard comprising a plurality of resilient, radially inwardly extending fingers.
 4. A drafting pen as in claim 3, said vent stem including: ii. at least one lateral fin engaging a corresponding stabilizing groove in said barrel; and iii. a lateral adjusting knob extending through a slot in the side of said barrel.
 5. A drafting pen as in claim 4, said slot in said barrel being elongated upon movement of said barrel cover.
 6. A drafting pen as in claim 5, said venting stem being spring-positioned within said barrel to an open vent position.
 7. A drafting pen as in claim 6, including: D. a cap securable about the bottom of said barrel so as to cover said writing point and urge said lateral adjusting knob upwardly to vent closed position.
 8. A drafting pen as in claim 7, said cap including: E. an ink reservoir communicant said writing point, or said cap placed over said writing point.
 9. A drafting pen comprising: A. a barrel enclosing an ink reservoir having a coaxially positioned bottom ink capillary passage leading to a writing point and a top venting passage; B. a venting stem including a side adjusting portion and Coaxially aligned top venting portion and bottom reciprocally positioned within said reservoir, so that said top valving portion is seated within said vent passage and said bottom cleaning wire end extends into said capillary passage, said top valving end including a plurality of serrations adapted to collect dried ink as said venting portion reciprocates in said vent passage, and said vent stem being positioned with said barrel such that said side adjusting portion is seated eccentrically with respect to said valving portion and includes a lateral adjusting knob extending through a slot in the side of said barrel.
 10. A drafting pen as in claim 9, said barrel having a plurality of longitudinal slots in its side, said slots being selectively alignable with said laterally adjusting knobs, so as to vary longitudinal extensibility of said venting stem.
 11. A drafting pen as in claim 10, said barrel being in separable top, middle and bottom components, such that extension of said bottom component with respect to said middle component provides a lateral filling port into said reservoir. 